1. Field of the Invention
The present invention relates generally to a transparent plastic container for storing medicinal agents formed into solid units, such as tablets, capsules, caplets, pills, and the like. More particularly, the transparent, light resistant container hereof includes a generally transparent wall structure of a predetermined thickness which permits visual inspection of the medicinal agents stored in the container, and inhibits transmission through the wall structure of light of a selected wavelength that could be detrimental to medicinal agents stored in the container. The present invention also relates to a resin used in forming the container which has dispersed therein a coloring agent, and an ultraviolet light radiation absorber which in combination, and correlated with the thickness of the wall structure, perform the unique function of precluding entry of undesirable light rays into the container while at the same time allowing visual observation of the contents of the container.
2. Description of the Prior Art
Presently, the United States Pharmacopeia (USP) includes regulations regarding certain properties of containers for storage of medicinal agents formed into solid units, such as tablets, capsules, caplets, pills, and the like. In USP 23, Section 661, entitled "Light Transmission Standards for UV Transmission", incorporated by reference herein, the USP requires that medicinal agents which are intended for oral or topical administration must be stored in a container which permits transmission into the container of no more than 10% of ultraviolet and visible light having a wavelength of between 290 nm to 450 nm. Light in this range potentially can be harmful to such medicinal agents during extended storage.
As a result, in the field of medicinal containers, most containers are generally formed from an opaque plastic in order to meet the USP requirements for light transmission. Such plastics inhibit the transmission through the container wall structure of light having a wavelength of between 290 nm and 450 nm. However, by virtue of the fact that these containers are opaque, transmission through the wall structure of visible light is also inhibited, preventing inspection of the medication in the container without opening the container.
State laws generally require that a licensed pharmacist verify that the medication in each container correspond with the label designation on the container before a filled container can be released to a patient. Therefore, the pharmacist must open each filled container and inspect the contents of such containers to verify that the proper medication is enclosed.
It is also known to provide an opaque covering for a generally transparent container. Once such a covered container is filled with the prescribed quantity of medicinal agents, the container is closed by a removable lid. Although the covering inhibits transmission through the container wall structure of undesirable light, transmission of visible light through the wall structure is also inhibited. As a result, the covering prevents inspection of the medication in the container without removing the lid.
A particular problem has arisen in recent years regarding use of opaque medicinal containers and coverings in automated filling of the containers with prescription medications. In prescription drug dispensing operations, such as those carried out by the Department of Veterans' Affairs where large numbers of containers filled with prescription medication are dispensed daily, the filling of containers has been highly automated. For example, it is now common to provide equipment which is capable of reading a bar coded label on each container and delivering the exact number of tablets or capsules into the container at the dispensing station, and to do so by directing a prescribed medication from a medication bin to the open container. A large number of different bins store medicine to be dispensed to the single filling station.
Lids are placed on each container as it emerges from the filling station and is moved along a conveyer line to protect the medication from contamination and spillage. Thus, a series of containers are directed by the conveyer or equivalent means to the final packaging or delivery area of the equipment. In most instances, each container holds a different medication and number of tablets or capsules therein.
Notwithstanding the efficiencies realized from automated filling of the containers, it is still necessary for a licensed pharmacist to remove the lid from each container (for example, a screw-top lid) and visually inspect the medication of each container to verify that the medication corresponds with the prescription represented by the bar coded label. In view of the fact that medicinal agents are commonly identified by size, shape, color patterns, and printed characters appearing on the surface of the tablets and capsules, the pharmacist can carry out the requisite inspection of the medication in prior art containers by removing the lid, and looking into the container to confirm that the medication does correspond with the prescription. Upon confirmation that the medication is correct, the lid must then be reattached to the container, so that the container may be released for shipment. If the medication does not correspond to the prescription, the medication is removed.
Removing and reattaching lids is an arduous and time consuming task, and is also wasteful of a pharmacist's time and is expensive. Furthermore, the mundane task of removing and reattaching lids by a pharmacist may also result in inattentiveness which may then lead to errors. Such errors can have dangerous consequences to patients receiving the medication, such as ingestion of improper medication. Additionally, the continual opening and closing of container lids may lead to contraction of medical problems by the pharmacist, such as carpal tunnel syndrome. Therefore a significant, and heretofore unsolved, need exists to provide a container for medicinal agents which meets the requirements of the USP, and which allows visual inspection of the medication in the container without removing the container lid.